• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.189-201
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• 1977

Some of basic aspects of soil potassium with special reference to soil physical properties were discussed. Data in the Official Soil Series Description(Korea) was analyzed according to soil type, land form, and soil texture to find soil potassium status which may explain different response to potassium application. Exchangeable potassium contents decreased with soil depth irrespective of soil type, land form and soil texture. Change in degree of potassium saturation within soil profile was not so clear as exchangeable potassium but the degree of potassium saturation of A horizon was highest among soil horizon. Soils of terrace and mountain foot slope showed high values both in exchangeable potassium and degree of potassium sauration and only these two soils were classified as soils having exchangeable potassium higher than 0.3 meq per 100g of soil and degree of potassium saturation higher than 5.0%. Exchangeable potassium of fine loamy and fine clayey soils is higher than 0.3 meq per 100g of soil but degree of potassium saturation is lower than 4.0%. Degree of potassium saturation of sandy soils exceeds 5.0% but exchangeable potassium is very low. Soils of rolling, hilly, unmatured and alpine land soils have lower exchangeable potassium and show lower degree of potassium saturation. The highest distribution of exchangeable potassium content irrespective of soil horizons was shown in the range of 0.1-0.2 meq per 100g of soil. The highest distribution of degree of potassium saturation was in the range of 2.0-3.0% in A horizon and 1.0-2.0% in B and C horizons. Of the soil series concerned in this analysis, 27.3% in A horizon, 11.1% in B horizon and 4.0% in C horizon had exchangeable potassium higher than 0.3 meq per 100g of soil and 18.0% in A horizon, 6.3% in B horizon, and 4.1% in C horizon showed degree of potassium saturation higher than 5.0%. The low response of potassium application only to soils in terrace and mountain foot slope may be resulted from the high exchangeable potassium content and high degree of potassium saturation. It is concluded that a great response of potassium application to soils is expected especially in dry season.

• Korean Journal of Materials Research
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• v.11 no.12
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• pp.1028-1034
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• 2001

The 2.5 vol% TiNi/6061Al composites were fabricated by permanent mold casting. The microstructures and tensile test for the cold rolled composites with maximum 50% reduction ratio were investigated. In the case of TiNi fiber with 2mm interval in preform, the interface bonding of fabricated composites were good, interface diffusion layer of this composites was made by the mutual diffusion. Transverse section of TiNi fiber was decreased with increasing reduction ratio and longitudinal section of TiNi fiber showed multiple wave phenomenon. And the tensile strength of composites at 38% reduction ratio was the most high. In the case of over 38% reduction ratio, the decrease of the tensile strength was due to TiNi fiber rupture by excess working. The fracture mode was appeared brittle fracture with increasing reduction ratio.

• Physical Therapy Korea
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• v.19 no.3
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• pp.1-10
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• 2012

The aim of this study is to compare measurements of abdominal muscle thickness using ultrasonography imaging (USI) to those using a special transducer head device, during five different trunk stabilization exercises, ultimately to determine which exercise led to the greatest muscle thickness. Thirty eight healthy subjects participated in this cross-sectional study. The five types of trunk stabilization - i.e., a sit-up on the supine, an upper and lower extremity raise with quadruped on the prone, a leg raise in sitting on the ball, trunk rolling on the ball, and balance using sling on the prone position - were each performed with an abdominal draw. The thickness of the abdominal muscle - including the transverse abdominal (TrA), internal oblique (IO), and external oblique (EO) - was measured by USI with a special transducer head device, at rest and then at contraction in each position. Data were analyzed using one-way repeated ANOVA with the level of significance set at ${\alpha}$=.05. The results were as follows: 1) the TrA thickness was statistically significant (p<.05), whereas the IO and EO thicknesses were not (p>.05); 2) among the five types of trunk stabilization, TrA thickness significantly increased with the balance using a sling in the prone position, (p<.05), whereas no significant difference was noted for the four types of trunk stabilization (p>.05); 3) reliability data showed that there was a high degree of consistency among the measurements taken using the special transducer head device (ICC=.92). In conclusion, the balance using a sling in the prone position was more effective than any of the four other types of trunk stabilization in increasing TrA thickness in healthy subjects.

• Korean Journal of Veterinary Research
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• v.29 no.3
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• pp.383-391
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• 1989

This study was carried out to diagnostic test for bovine mastitis by the determination of adenosine triphosphate (ATP) based on firefly bioluminescence. The results obtained are follow; 1. The infection rate of bovine mastitis investigated with 521 cows in 47 dairy farms were found to be 3.6% of clinical form and 44.1% of subclinical form according to the degree of infection. 2. The light yield produced in firefly bioluminescence system was proportional to the concentration of ATP giving stright line within the range of 100PM~1uM. 3. When the number of somatic cell in milk was determined by the ATP assay and compared with three conventional methods such Fossomatic, California mastatic test (CMT), and rolling ball viscometer (RBV), it was shown that r=0.92 for Fossomatic, 0.63 for CMT and 0.7 for RBV. 4. The microorganisms causing mastitis were isolated Staphylococcus sp. (53.3%), Streptococcus sp. (17.9%), Micrococcus sp. (13.5%), Gram negative bacilli (6.3%), Gram positive bacilli (5.5%) and Yeast-like fungi (5.4%). 5. The endogeneous ATP levels of bacteria in a raw milk determined by the firefly bioluminescence system and compared with the results of the conventional methods. The correlation was 0.88 for raw milk.

• Journal of Welding and Joining
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• v.31 no.5
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• pp.47-53
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• 2013

We have investigated the traits of clad metals in hot-rolled clad steel plates, including the sensitization and mechanical properties of STS 316 steel plate and carbon steel (A516), under various specific circumstances regarding post heat treatment, multilayered welds, and thick or repeated welds for repair. For evaluations, sectioned weldments and external surfaces were investigated to reveal the degree of sensitization by micro vickers hardness, tensile, and etching tests the results were compared with those of EPR tests. The clad steel plates were butt-welded using FCAW and SAW with the time of heat treatment as the variable, a that was conducted at $625^{\circ}C$, for 80, 160, 320, 640, and 1280 min. Then, the change in corrosion resistance was evaluated in these specimens. With carbon steel (A516), as the heat treatment time increased, the annealing effect caused the tensile strength to decrease. The micro-hardness gradually increased and decreased after 640 min. The elongation and contraction of the area also increased gradually. The oxalic acid etch test and EPR test on STS316 and the clad metal showed STEP structure and no sensitization. From the test results on multi-layered and repair welds, it could be concluded that there is no effect on the corrosion resistance of clad metals. The purpose of this study was to suggest some considerations for developing on-site techniques to evaluate the sensitization of stainless steels.

• Progress in Superconductivity
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• v.7 no.2
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• pp.145-151
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• 2006

Nickel and nickel-tungsten alloy were electroplated on a cold rolled and heat treated copper(Cu) substrate. 4 mm-thick high purity commercial grade Cu was rolled to various thicknesses of 50, 70, 100 and 150 micron. High reduction ratio of 30% was applied down to 150 micron. Rolled texture was converted into cube texture via high temperature heat treatment at $400-800^{\circ}C$. Grain size of Cu was about 50 micron which is much smaller compared to >300 micron for the Cu prepared using smaller reduction pass of 5%. 1.5 km-long 150 micron Cu was fabricated with a rolling speed of 33 m/min and texture of Cu was uniform along length. Abnormal grain growth and non-cube texture appeared for the specimen anneal above $900^{\circ}C$. 1-10 micron thick Ni and Ni-W film was electroplated onto an annealed cube-textured Cu or directly on a cold rolled Cu. Both specimens were annealed and the degree of texture was measured. For electroplating of Ni on annealed Cu, Ni layer duplicated the cube-texture of Cu substrate and the FWHM of in plane XRD measurement for annealed Cu layer and electroplated layer was $9.9^{\circ}\;and\;13.4^{\irc}$, respectively. But the FWHM of in plane XRD measurement of the specimen which electroplated Ni directly on cold rolled Cu was $8.6^{\circ}$, which is better texture than that of nickel electroplated on annealed Cu and it might be caused by the suppression of secondary recrystallization and abnormal grain growth of Cu at high temperature above $900^{\circ}C$ by electroplated nickel.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.8
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• pp.180-188
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• 2000

Fine multi-hole sheet metal product(FMSMP) is a specific metal plate which is used in color TV and computer monitor. Processes of manufacturing FMSMP are generally composed of coating cleaning exposure and etching processes. After a thin metal plate is made by rolling photosensitive liquid is coated on the metal plate in coating process. Then the coated thin metal plate consecutively passes through exposure process in which upper and lower glasses are compressed by vacuuming the space between glasses and metal plate. In this lowered glasses are compressed by vacuuming the space between glasses and metal plate. In this lowered vacuum state certain part of metal plate is desirably exposed to light and will be etched into forming lots of well-arranged holes with a specific diameter, nowadays to manufacture FMSMP of 17 inch braun tube 80 second is required for complete vacuum but 35 second is applied to manufacture FMSMP in reality. In the present study vacuuming time is tried to reduce for improvement of productivity by analyzing vacuum system and proposing several solutions, for faster vacuuming speed degree of vacuum state between glasses and metal plate is improved by the proposed method and experiments using the proposed method are performed for verification. In addition microstructure of FMSMP is investigated to prevent stain phenomena and to improve quality of the product.

• Tribology and Lubricants
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• v.33 no.3
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• pp.119-125
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• 2017

In this study, we perform a numerical analysis to predict the film thickness and lubrication regions for a thrust ball bearing under different operating conditions. Film thinning and replenishment affect the film thickness in starved lubrication. As the inlet meniscus position is brought to the edge of the Hertz contact, the thin film thickness is calculated as starved equation. We use a film replenishment model to determine the recovery film thickness between rolling elements. We use a hydrodynamic model to describe film recovery, that results from the effects of surface tension. In this model, we consider the surface tension gradient in fluid depression as the driving force for fluid recovery. We use Fourier transform method to determine the time-dependent depth of depressed oil. We calculate the change in the central film thickness graphically by using the recovery equation in starved elastohydrodynamic lubrication(EHL) under operating conditions that include numbers of balls, sliding velocity, applied force, and ambient film thickness. We evaluate the degree of starvation by using the distance from the center of the contact area to the meniscus position. Parched lubrication, a phenomenon where the film thickness decreases consistently, occurs at the severe condition. We determine optimal values with respect to the numbers of balls, and sliding velocity. The investigation can contribute to the design operating conditions for proper lubrication.

• Journal of the Korean Society of Fashion and Beauty
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• v.1 no.1 s.1
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• pp.105-118
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• 2003

The purpose of this study was to analyze entertainer Byeon Jeong-su's hair styles and thereby, apply the results to models. For the applications, models' hair styles were bisected into two sections, and thereby, the edges of the outsides were cut into solid points, and thereupon, into diverse bases by using vertical section, Perpendicular direction and square angles. On the other hand, the insides were cut in the same way of the outside bases by using radial section, varied combing and $45{\sim}90$ degree head angles. In addition, tops and sides were arranged in their corners, while a graduation technique was used to express a natural difference of levels. The fringes were cut by using free-hand and slicing techniques. furthermore, the quantity and mass of the hairs were treated with such techniques as thinning, swing, effect, rolling, slide and slicing, while a bridge product was used for coloring together with a highlight technique. The hair styles were rendered for straight and wave by using an magic iron machine. It was confirmed through this study that the same cutting techniques would result in different images depending on individuals' physical shapes, facial shapes, head skeletons and types of hairs. Thus, it is required of the hair designers to suggest their own custom hair designs adequate to individuals' images through continued image-wise hair design practices.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.25 no.4
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• pp.80-88
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• 2012

Background and Objective : Atrophic scars are the most common complication of acne. Many modalities are proposed but each does not yield satisfactory clinical outcomes. Among therapeutic modalities of acne scars, subcision is a simple, safe procedure with a different and basic mechanism for correcting atrophic and depressed scars. However, there are few reports about such procedure. This study performed to evaluate the effect of subcision treatment on atrophic acne scar. Methods : Five patients with atrophic acne scars of various types(rolling, superficial and deep boxcar, pitted and icepick) were treated by superficial dermal undermining with 25~27 gauge needles. We used GASC(Global Acne Scarring Classification). Satisfaction degree was asked from the patients. Results and Conclusions : After observing patients satisfaction, comparing case photos and GASC, it can be considered that subcision treatment brings great results when performed on atrophic post acne scars.